LS, Discospondylitis, Rando Flashcards
Antibiotic recommended for bacterial encephalomyelitis?
metronidazole, enrofloxacin, chloramphenicol, TMS, 3rd gen cephalosporin
antibiotic recommended for discospondylitis?
1st gen cephalosporins (clavamox sound) - 17% Staph resistant
Cephalexin, cefazolin, TMS
what dog breeds most often diagnosed with disconspondylitis? prognosis?
Great Dane, Labs, Rott, GSD, Doberman, Eng Bulldogs
fair to good uncomplicated
what are complications of sx for LSS?
trauma, compression, implant failure, inadequate bony fusion, adjacent segment disease
infections (23% positive cultures of disc)
seroma
instability
neuro deterioration
what is the overall prognosis?
excellent to good 77% (some papers report higher)
73% (Dorsal lam + discectomy)
what is recurrence rate?
3-54.5% (one study 16.7% normal function, 54% if only had mild improvement)
compare presentations of BP avulsion injuries:
1) avulsion cranial (C5-C7)
2) avulsion caudal )C8-T2)
3) all (C6-T2)
1) musculocutaneous, axillary, subscapular, suprascapular
- loss of shoulder movement and elbow flexion
- few CS
2) radial, median, ulnar (radial nerve signs more common - 92% of cases)
- flexed limb but no weight bearing as can’t extend carpus/digits
- Horner’s and/or loss cutaneous trunci (C8-T1)
3) all nerves
- drag limbs knuckled over, shoulder more neutral
- sensory deficits common
what are signalment/common breeds that get steroid-responsive menigitis-arteritis?
young 6-18 months
74.2% are < 1year
Beagles, boxers, BMD, weimaraners, Nova scotia duck retrievers
presentation and CSF findings between the 2 forms (steroid-responsive menigitis-arteritis)?
acute form:
- hyperesthesia, cervical rigiditly, stiff gait, fever
- guarding neck
- polymorphonuclear nondegenerative, pleocytosis, increased TP, ~ RBC
chronic form:
- paresis, ataxia, menace deficit, anisocoria, vestibular signs
- primary mononuclear cells or mixed cells, normal or mildly increased TP
what BW can help to monitor therapy (steroid-responsive menigitis-arteritis)?
acute form:
-c-reactive protein
chronic form:
- macroglobulin
what are the components and locations of ventriculoperitoneal shunt?
ventricular catheter
control valve
abdominal or distal catheter
ventriculoperitoneal shunt - complications of placement?
shunt infection, shunt malfunction/blockage, under shunting, catheter migration, control valve function, seizures
what are the systems described to evaluate brain sx post-op?
response criteria in solid neoplasms (RECIST)
response assessment in neuro-oncology (RANO)
MacDonal criteria
what is diagnostic yield for stereotactic biopsy? morbidity rates?
> 90% especially for cancer
morbidity rates up to 27% reported (but newer rates ~5%)
what are high risk breeds of LSS?
GSD, Dobie, Rottie, BMD, Dalmation, Boxer, Irish Setter, lab
what is intermittent claudication?
paroxysmal manifestations - caudal lumbar pain or PL cramping, pain, weakness from vascular compromise or compression of nerve roots of cauda equina
what C.S/presenting complaint in dog with LSS have worse prognosis?
urinary and/or fecal incontinence
what congenital cranium abnormalities may benefit from sx?
intracranial arachnoid diverticula
dermoid/epidemoid cysts
congenital hydrocephalus
disorders associated with malformation of caudal cranial fossa and craniocervical junction
Signalment for calcinosis circumscripta?
< 1yr, large breed. (GSD overrepresented)
prognosis with surgery for calcinosis circumscripta?
no recurrence upto 24 mo post dorsal laminectomy
what causes osteochondroma?
arise secondary to migration of chondrocytes from physeal region into metaphyseal region of bone
continued cartilage formation
prognosis for osteochondroma?
if a accessible to excise - favorable
what are the 3 stages of distemper infection?
gray matter disease:
- ~1 week post infection - nonsuppurative ME
- often die within 2-3 weeks (often with seizures)
- may recover or progressive to next
white matter disease:
- ~3 weeks post infection
- most common form (likely due to subclinical GM stages)
- may recover with minimal CNS injury or infection
necrotizing meningoencephalitis
- ~4-5 weeks post infection
- nonsuppurative inflammation
- uveitis, chonoretinitis
some deteriorate and die; others slowly recover
distemper infection - diagnostics? treatment?
RT - PCR (whole blood, urine, CSF)
IHC antigen biopsy - nasal mucosa, foot pad epithelium, haired skin
supportive treatment
prognosis guarded
list surgical techniques for treating brachial plexus avulsions
neurotization (re-enervation of denervated motor or sensory end organ (sacrifice donor nerve))
reimplantation - through hemilaminectomy
end to end suturing/anastomosis (without graft)
what is the prognosis for avulsion injuries to the brachial plexus?
grave if radial nerve avulsion
give case 4-6 weeks until grave prognosis is given
what is a myelodysplasia dysraphism?
congenital malformation - incomplete and abnormal fusion of neural tube win sagittal plane - bunny hopping
what breed is predisposed to a myelodysplasia dysraphism ?
weimaraner
what is the treatment for a myelodysplasia dysraphism?
no treatment
not in pain and doesnt progress
what are methods of cranial reconstruction, protection of meninges?
Meninges:
direct suturing
fascia temporalis
porcine SIS
Cranium:
Replacement of excised skull bone or calvarial allografts
acrylic cranioplasty
metallic mesh
what is most informative/sensitive test for evaluating cauda equine syndrome?
somatosensory evoked potenitals
list four variant radiographic studies that can be used to evaluate LSS
advantages/disadvantages of each?
venography - can have tech errors
myelography - limited due to location of enddural sac (cant evaluate LS IVD vs LS IV foramen)
epidurography - easier/superior to myelographs and less side effects
discography - inject into NP; could lead to IVD degeneration
for LS fracture/subluxation - affected dogs can have up to ____% displacement of canal without major neuro deficits
100%
list reported techniques to repair LS fractures
- transilial pinning
- modified segmental spinal instrumentation
- combined Kirschner-ehmer/dorsal spinal plate fixation
- pins/screws and PMMA
- locking plate (SOP)
where to focus pins on LS fracture?
cranial - implants intact pedicles and body L7
caudal - implant sacrum, tuber sacrale, body of ilium
what are the 2 approaches to pituitary?
transcrally (transphenioidally)
ventral paramedian
list complications to (short vs long) of cranial sx?
short term:
- aspiration pneumonia
- seizures
- recurrence intracranial bleeding
- increased ICF
long term:
- infection
- pneumocephalus
- compression brain secondary to fibrous tissue or overlying musculature
what is the difference in pathophysiology for non communication, communicating, and compensatory for secondary hydrocephalus?
non communicating: obstruction of flow from ventricles to SAS
communicating: decreased resorption by arachnoid villi or increased production of CSF
compensatory: loss of brain parenchyma
list three approaches to foraminotomy: advantages vs disadvantages
dorsal laminectomy:
- to see IV foramen.
- can’t see L7 nerve root exit well
lateral approach:
- with foraminotomy created from lateral side and direct to vertebral canal.
- dont directly observe cauda equina. - tough to see entry zone of foramen
osteotomy of wing of ilium:
- not used yet
lateral approach:
- access IVD and foramen and dont affect ZPJ
how can you improve visibility for foraminotomy for dorsal laminectomy?
remove medial part of caudal articular process L7
durotomy decreases ICP by ___% versus 15% by craniotomy alone?
65%
which vertebral neoplasms are chemo responsive or at least reported to be?
lymphoma, plasma cell tumor, OSA, multiple myeloma
list extradural noeplasma of vertebra?
osa, lymphoma, histiocytic sarcoma complex, infiltrative lipoma, myxoma, calcinosis circumscripta, osteochondroma, chondrosarcoma
list intradural/extramedullary neoplasms of vertebra?
meningioma, nerve sheath tumor, extrarenal (ependymoma, neuropeithelioma)
list intramedullary tumors of vertebra?
ependyma, glia for primary origin, metastatic for secondary, astrocytoma
what breeds are overrepresented with histiocytic sarcoma complex?
Bernese mt dogs, golden, rott, flat-coated retriever
MST for histiocytic sarcoma complex?
3-4 months
recurrence rate of infiltrative lipoma
36-50%
what is a myxoma? breeds that are overrepresented?
rare tumor of synovium
dobies and labs.
ventrolateral stabismus from what nerve injury?
oculomotor
medial stabismus fro what nerve injury?
abducens
eyeball extersion (rotation) from what nerve injury?
trochlear
lateral rotation of dorsal pupil in cats?
trochlear
what is the function of CN IX-XII?
IX: glossopharungeal - sensory and motor to pharynx
X: vagus - sensory and motor to pharynx, larynx, and viscera
XI: Accessory:
- external branch - trapezius
- internal branch - joint CN X to innervate larynx
XII: hypoglossal - motor to tongue
For junctionapathies, what are motor units involved with:
- presynaptic
- synaptic
-postsynaptic
pre - transmitter synthesis and/or release
synaptic - acetylcholinesterase
post - acetylcholine receptor
what/describe classifications of nerve injury?
Class 1: neuropraxia - interrupt function and conduction of nerve without structural changes; reversible
Class 2: axonotmesis - crush and percussion ( internal architecture of nerve preserved - good recovery )
Class 3: neurotmesis - disruption axon/endoneurium but intact perineurium)
Class 4: neurotmesis - disruption axons, endoneurium, perineurium
Class 5: neurotmesis - nerve is severed
Class 6: combines others per fascicle
what is the purpose of balanced steady - state?
cardiac, orthopedic, and T2-like applications - high contrast of fluid structures.
useful for CNs, inner ear, CNS movement and assessing CNs as course through subarachnoid space
what has been suggested as risk factors for UTI post op treatment IVDD?
need for bladder evacuations (not catheterization)
prophylactic use of antibiotics during catheterization
NOT sex
what are acceptable postvoid US urinary bladder diameters?
dogs <30kgs - 3 cm
dogs >30kgs - 4-5 cm
what is the normal range of ICP?
5-12 mmHg
what is normal cerebral blood flow?
75.9ml/min/100g
autoregulation falls in MAP <___mmHg?
MAP < 60mmHg
PaCO2 should be kept ~_______ mmHg?
30 mmHg
PaO2 has effect on CBF once <____mmHg?
50 mmHg
what is normal dog cerebral metabolic rate? how much make ATP?
3.5 ml/min/100g (60% to make ATP)
what is the benefit of a spoiled gradient echo?
produce T1W images faster
also can use with T2 to detect stages of Hb without blood clot
what is the benefit of diffusion-weight imaging? perfusion imaging?
demonstrates restricted diffusion of H2) in ischemic strokes or cell neoplasm, abscesses, epidermoid cyst, cholesteatomas
helps for stroke management
list congenital/developmental anomalies of AA joint
dysplasia (34%),
hypoplasia or aplasia (46%)
dorsal angulation
separation of dens
absences of transverse ligament
incomplete ossification atlas
block vertebrae
what breeds most commonly affected by AAI?
yorkies, chi, mini poodles, poms, pekingese (large breed - poodles)
what % of dogs with AAI have postural reaction abnormalities?
56%
what % are tetraplegic?
what % have gait abnormalities
40%
94%
what is the lateral vertebral foramen?
perforates craniodorsal part of vertebral dorsal arch of atlast
what passes through lateral vertebral foramen?
1 st cervical nerve and vertebral artery? (Tobias just says vasculature)
what are the ligaments that attach to the dens?
apical ligament - attaches to basiooccipital bone
bilateral alar ligament - attached to occipital condyles
what ligaments that attach to the dens are most important to protect against VD shearing forces?
alar
what % of cervical function are C1/C2?
50-70%
what is periop mortality rate for surgical treatment of cervical fracture?
10-35%
what is the most common cause of death for cervical fracture? second most common?
cardiopulmonary arrest
respiratory dysfunction
what is the average ideal insertion angle for C3-C6 vertebrae? (Watire 2006) C7?
34.2 - 37.5%
C7 - 47.5%
what is the morbidity rate for dorsal laminectomy for CSM?
65-78% will be worse postop
what are risk factors for high rate of morbidity?
diagnosis of osseous associated, more severe neuro status, prolonged sx time.
success rate for dorsal laminectomy?
79-95%
% of recurrence rate followin dorsal laminectomy?
30%
what were original pin trajectories for cervical fracture repair?
~20-35%
what CT finding simulation show violated vertebral canal at 30, 35, 40 degrees?
30 - 58%
35 - 41%
40 - 33%
describe pins insertion for C2 specifically?
craniolateral direction C2 - C1
30-35% in sagittal plane
40-45% transverse
use point just medial to alar notch and transverse foramen C1)
Caudal C2 - lateral 30-50%
what is prognosis for AAI treatment (conservative)? mortality rate?
38% good outcome with medical management
mortality 4-30%
outcome for dorsal vs ventral AAI treatment
dorsal:
- good to excellent 61%
- dorsal wire loop 52% success
- Kishlgromi 75% toy breed excellent
ventral:
- good to excellent 47-92%
-transcutaneous pin alone - 47%
-pins + PMMA - neuro improvement 94%. complication 34%
- transarticular screw lag fashion 90% success in one study; 40% in another
what are some risk factors for outcome reported?
age of onset SA with odds success
duration (<10months)
severity of clinical signs SA with odds success
what % have single site in large vs giants dogs for CSM?
50% single site - large breed
20% single site - giant breed
what is the most common site?
C6-C7 most common (large breed)
(giant breeds) 80% being one of the sites in C4-C7
what % reported T1-T2 and C7-T1 CSM?
T1-T2 - 14.3% giant breeds
C7-T1 22.8% all dogs
how often is nerve root signature present in cervical IVDD?
22-50%
what % are cervical IVDD acute onset?
45%
what % of cervical IVDD patients are :
- non ambulatory tetraparesis?
- ambulatory tetraparetic
- tetraplegia
non ambulatory - 11-22%
ambulatory - 42%
tetraplegia - 2-7%
what % of cervical IVDD patients have reduced/absent reflex with cranial lesions?
34% (usually dogs < 10kg)
what are reported complications of CSM (cervical spondylomyelopathy) surgery? rates?
- neuro deterioration (dorsal - 70%, ventral 42%)
- vertebral forament/transverse foramina penetration 25-57%
- adjacent segment syndrome (domino effect); 20% primary with distraction and stabilization techniques; ventral slot decreases risk occurrence
- laminectomy membrane (incidence unknown)
- implant failure (dist/fusion technique 7.5%-30%)
- collapse of intervertebral foramina
- insufficient decompression
list complications of stabilizing AAI
- neuro deterioration ( manipulation or implant placement)
- respiratory compromise:
1) trauma to laryngeal nerve
2) compound BOAS
3) tracheal compression
4) tracheal necrosis
5) aspiration pneumonia - implant failure
-fracture of atlas or axis - recurrent pain
- persistent neuro deficits
what are general complication rates up to ____ for dorsal vs ventral?
dorsal - 71%
ventral - 53%
list decompressive techniques for CSM?
DIRECT:
V slot
dorsal laminectomy
hemilaminectomy
dorsal laminoplasty
INDIRECT:
vertebral distraction
list methods of distraction-stabilization for CSM?
Pins and PMMA
screw-bar PMMA
PMMA plug (w or w/o retention screw)
LCP
titanium cage and screw
IV spacer with screw
IV traction screw
IV cage
what is one motion-pressuring technique for treatment of CSM?
cervical disc arthroplasty
what is spina bifida:
occulta
cystica
aperta
occulta: no external evidence of malformation (skin dimple/whorling of hair)
cystica: concurrent existence fo meningocele, meningomyelocele, myeloschisis
aperta: open dysraphic/mylodysplastic disccidas
Manx, screw tail breeds
what is a dermoid sinus? common breed?
skin doesn’t separate from neural tube
Rhodesian ridgebacks
Burmese
Describe pin placement for pin + PMMA stabilizing of T-L fractures?
entry point T spine - level accessory process/tubercle of rib
entry point L spine - level between base of transverse process and accessory process
pin direction lateral to medial dorsal to ventral
- direct cranial for cranial vertebrae
- direct caudal to caudal vertebrae
Advantages of pin + PMMA stabilizing of TL fracture
seats pins within vertebra closer to end plates where vertebral body widest
list methods of stabilizing L7-S1 unit for LSS
- screws/pins + PMMA (in body L7/sacrum)
- dorsal cross pin
- cortical screws lag fashion across ZPJ
- SOP Plate
- pedicle screw rod fixation
- intrabody fusion device
Methods for stabilizing L7-S1 using transarticular screws? what are the guidelines?
direct ventrolateral 30-45% relation to sagittal
depth hole not beyond body of sacrum
screw diameter 25% of diameter of articular process
what is in rostrotentorial compartment? most common surgical approach?
- cerebral hemispheres, thalamus, hippocampus, olfactory
- transfrontal (+/- modified), transphenoidal
- other - unilateral rostrotentorial (+/- zygomatic ostectomy)
what is in caudotentorial compartment? most common surgical approach?
- cerebellum, pons, medulla, 4th ventricle
- suboccipital +/- occlusion transverse venous sinus
- RARE - ventral to caudal brainstem
what do you need to avoid when doing transverse sinus occlusion?
dont occlude confluens sinuum
L7-S1 is what type of joint?
amphiarthrodial - cartilaginous
list components that can make up degenerative LS stenosis
-Hansen type 2 IVDD
-transition vertebrae
-congenital stenosis of canal or IV foramina
-sacral osteochondrosis
-proliferation of joint capsule or ligaments
- osteophytosis of articular processes
-epidural fibrosis
- instability of/malalignment/subluxation of L7-S1
what is iodine contrast dose for brain IV?
Brain 400-500mg iodine/kg
what is dose for CT myelogram full vs regional? max volume to give?
myelogram:
FULL - 0.45 ml/kg
REGIONAL - 0.3 ml/kg
avoid >8ml to avoid risk of seizures
what are 3 forms of granulomatous ME?
disseminated - rapidly progressive multifocal neuro signs
focal - uncommon; slowly progressive - single space lesion
ocular - acute onset visual impairment; variable pupillary changes; optic nerve swelling
what the clinical signs of the 3 forms of granulomatous ME? treatment? prognosis?
immunosuppressives (pred, cytosine arabinoside, procarbazine, cyclosporine, mycophenolate, etc)
generally poor long term. favorable short term
focal form survive longer than disseminated form
what is prognosis of LS disease with medical management
55-79% reported
55% - with NSAID and gabapentin
79% - with epidural methylpred
what is surgical treatment for LSS? what are supplemental procedures?
dorsal laminectomy
+/- partial discectomy (dorsal annulectomy and nuclear pulpectomy)
+/-foraminotomy
+/- removal of zygapophyseal joint with stabilization post
Lymphoma of spine:
in cats
- what % of all confirmed spinal cord disease is lymphoma
- what % of all neoplasm in spinal cord is lymphoma?
27% of all spinal cord disease
25-38% neoplasms in spinal cord is lymphoma
In cats:
what disease is often associated with lymphoma in cats spinal cord?
FeLV
what is the prognosis for dogs with lymphoma of spine
very poor
what is the response rate for cats with spinal lymphoma with chemo? MST?
70-100%
MST <5-7 months; some >1 year
what is the monro-kellie doctrine?
features of cranium - increase in volume of one component requires reciprocal decrease in one or more of the others to keep ICP
describe differences in tissue attenuation and intensities of T1W vs T2W
T1W:
short relax (fat) - bright
long relax (CSF) - dark
normal tissue - grays
other brights: metHb, hemorrhage, mucin, tissues, melanin, ion deposits
T2W:
short relax (muscle) - dark
long relax (CSF) - bright
intermediate (fat) - intermediate
normal tissue - grays
white malta hypointense to gray
other brights: edema, necrosis, cell infiltrate (neoplasm, inflammation)
